Feeding studies of dietary diacylglycerol oil in normal and lipoprotein lipase-deficient cats

The entire dissertation/thesis text is included in the research.pdf file; the official abstract appears in the short.pdf file (which also appears in the research.pdf); a non-technical general description, or public abstract, appears in the public.pdf file."December 2008"Thesis (M.S.) University of Missouri-Columbia 2008.Diacylglycerol (DAG) oil has been investigated in humans and animals as a potential therapy for hypertriglyceridemia and related disorders. DAG oil was evaluated in healthy cats and in a feline model of hypertriglyceridemia as a result of lipoprotein lipase (LPL) deficiency. In the first study, eight adult cats were offered a commercial dry diet enriched with either DAG or triglyceride (TAG) oil (48% metabolizable energy [ME] from fat) in a two-bowl palatability feeding trial. After 14 days, total food intakes were similar (DAG diet 470 [plus or minus]52 g, TAG diet 380 [plus or minus]88 g, P = 0.4). Both diets were well-accepted and no changes in health or fecal quality were observed. In the second study, eleven adult LPL-deficient male cats were fed a semipurified diet containing either DAG or TAG oil as the sole fat source (25% ME) in a crossover design for 8 days each after a 21-day acclimation period. Serum concentrations of TAG, cholesterol, and nonesterified fatty acids were measured on days 6, 7, 8 and days 14, 15, 16. No significant effects were observed on any measurements, and a reduction in hypertriglyceridemia was not demonstrated (DAG: 3282 [plus or minus]400 mg/dl, TAG: 3001 [plus or minus]302 mg/dl). Dietary fat source did not significantly affect food intake, body weight, fecal quality, or general health. Further studies of DAG oil in cats are needed to evaluate long-term safety and benefits.Includes bibliographical reference

STUDY OF THE FLUXSET MAGNETIC PROBE SPEED–SENSITIVITY DEVELOPED FOR DETECTION OF MAGNETIC NANOPARTICLES IN SURGERY

Markers for imaging are vital parts of surgical processes. S ince radioactive compound pose considerable risk to both the recipient and the surgical staff, alternative marking te chniques are of interest. In NANOMAGDYE project, magneto- optically active nano-particles were created for this reas on. The detection of the magnetic interaction of low mass nan o- particles in surgical environment is very challenging; so f ar only quasi-stationary measurements were taken. This pap er shows a measurement setup for measurements with continuous ly moving probe at lower velocities (5–10 mm/s) and at hand movement velocity (20–30 cm/s). It was found that at the velo city of hand movement there is only probe response amplitude reduction of at most 10–15 % of the original amplitude. These results indicate that the probe used for the detection of the nano-particles is sufficient to be used in practical purposes in surgery

Hit and run versus long-term activation of PARP-1 by its different domains fine-tunes nuclear processes.

Poly(ADP-ribose) polymerase 1 (PARP-1) is a multidomain multifunctional nuclear enzyme involved in the regulation of the chromatin structure and transcription. PARP-1 consists of three functional domains: the N-terminal DNA-binding domain (DBD) containing three zinc fingers, the automodification domain (A), and the C-terminal domain, which includes the protein interacting WGR domain (W) and the catalytic (Cat) subdomain responsible for the poly(ADP ribosyl)ating reaction. The mechanisms coordinating the functions of these domains and determining the positioning of PARP-1 in chromatin remain unknown. Using multiple deletional isoforms of PARP-1, lacking one or another of its three domains, as well as consisting of only one of those domains, we demonstrate that different functions of PARP-1 are coordinated by interactions among these domains and their targets. Interaction between the DBD and damaged DNA leads to a short-term binding and activation of PARP-1. This hit and run activation of PARP-1 initiates the DNA repair pathway at a specific point. The long-term chromatin loosening required to sustain transcription takes place when the C-terminal domain of PARP-1 binds to chromatin by interacting with histone H4 in the nucleosome. This long-term activation of PARP-1 results in a continuous accumulation of pADPr, which maintains chromatin in the loosened state around a certain locus so that the transcription machinery has continuous access to DNA. Cooperation between the DBD and C-terminal domain occurs in response to heat shock (HS), allowing PARP-1 to scan chromatin for specific binding sites

Comparison of quantum mechanical and classical trajectory calculations of cross sections for ion-atom impact ionization of negative - and positive -ions for heavy ion fusion applications

Stripping cross sections in nitrogen have been calculated using the classical trajectory approximation and the Born approximation of quantum mechanics for the outer shell electrons of 3.2GeV I$^{-}$ and Cs$^{+}$ ions. A large difference in cross section, up to a factor of six, calculated in quantum mechanics and classical mechanics, has been obtained. Because at such high velocities the Born approximation is well validated, the classical trajectory approach fails to correctly predict the stripping cross sections at high energies for electron orbitals with low ionization potential.Comment: submitted to Phys. Rev.

Development of a thermal ionizer as ion catcher

An effective ion catcher is an important part of a radioactive beam facility that is based on in-flight production. The catcher stops fast radioactive products and emits them as singly charged slow ions. Current ion catchers are based on stopping in He and H$_2$ gas. However, with increasing intensity of the secondary beam the amount of ion-electron pairs created eventually prevents the electromagnetic extraction of the radioactive ions from the gas cell. In contrast, such limitations are not present in thermal ionizers used with the ISOL production technique. Therefore, at least for alkaline and alkaline earth elements, a thermal ionizer should then be preferred. An important use of the TRI$\mu$P facility will be for precision measurements using atom traps. Atom trapping is particularly possible for alkaline and alkaline earth isotopes. The facility can produce up to 10$^9$ s$^{-1}$ of various Na isotopes with the in-flight method. Therefore, we have built and tested a thermal ionizer. An overview of the operation, design, construction, and commissioning of the thermal ionizer for TRI$\mu$P will be presented along with first results for $^{20}$Na and $^{21}$Na.Comment: 10 pages, 4 figures, XVth International Conference on Electromagnetic Isotope Separators and Techniques Related to their Applications (EMIS 2007